This class loader is used to load classes and resources from a search
path of URLs referring to both JAR files and directories. Any URL that
ends with a '/' is assumed to refer to a directory. Otherwise, the URL
is assumed to refer to a JAR file which will be opened as needed.

The AccessControlContext of the thread that created the instance of
URLClassLoader will be used when subsequently loading classes and
resources.

The classes that are loaded are by default granted permission only to
access the URLs specified when the URLClassLoader was created.

Constructor Detail

URLClassLoader

Constructs a new URLClassLoader for the given URLs. The URLs will be
searched in the order specified for classes and resources after first
searching in the specified parent class loader. Any URL that ends with
a '/' is assumed to refer to a directory. Otherwise, the URL is assumed
to refer to a JAR file which will be downloaded and opened as needed.

If there is a security manager, this method first
calls the security manager's checkCreateClassLoader method
to ensure creation of a class loader is allowed.

Parameters:

urls - the URLs from which to load classes and resources

parent - the parent class loader for delegation

Throws:

SecurityException - if a security manager exists and its
checkCreateClassLoader method doesn't allow
creation of a class loader.

URLClassLoader

Constructs a new URLClassLoader for the specified URLs using the
default delegation parent ClassLoader. The URLs will
be searched in the order specified for classes and resources after
first searching in the parent class loader. Any URL that ends with
a '/' is assumed to refer to a directory. Otherwise, the URL is
assumed to refer to a JAR file which will be downloaded and opened
as needed.

If there is a security manager, this method first
calls the security manager's checkCreateClassLoader method
to ensure creation of a class loader is allowed.

Parameters:

urls - the URLs from which to load classes and resources

Throws:

SecurityException - if a security manager exists and its
checkCreateClassLoader method doesn't allow
creation of a class loader.

URLClassLoader

Constructs a new URLClassLoader for the specified URLs, parent
class loader, and URLStreamHandlerFactory. The parent argument
will be used as the parent class loader for delegation. The
factory argument will be used as the stream handler factory to
obtain protocol handlers when creating new jar URLs.

If there is a security manager, this method first
calls the security manager's checkCreateClassLoader method
to ensure creation of a class loader is allowed.

Parameters:

urls - the URLs from which to load classes and resources

parent - the parent class loader for delegation

factory - the URLStreamHandlerFactory to use when creating URLs

Throws:

SecurityException - if a security manager exists and its
checkCreateClassLoader method doesn't allow
creation of a class loader.

close

Closes this URLClassLoader, so that it can no longer be used to load
new classes or resources that are defined by this loader.
Classes and resources defined by any of this loader's parents in the
delegation hierarchy are still accessible. Also, any classes or resources
that are already loaded, are still accessible.

In the case of jar: and file: URLs, it also closes any files
that were opened by it. If another thread is loading a
class when the close method is invoked, then the result of
that load is undefined.

The method makes a best effort attempt to close all opened files,
by catching IOExceptions internally. Unchecked exceptions
and errors are not caught. Calling close on an already closed
loader has no effect.

IOException - if closing any file opened by this class loader
resulted in an IOException. Any such exceptions are caught internally.
If only one is caught, then it is re-thrown. If more than one exception
is caught, then the second and following exceptions are added
as suppressed exceptions of the first one caught, which is then re-thrown.

getURLs

Returns the search path of URLs for loading classes and resources.
This includes the original list of URLs specified to the constructor,
along with any URLs subsequently appended by the addURL() method.

definePackage

Defines a new package by name in this ClassLoader. The attributes
contained in the specified Manifest will be used to obtain package
version and sealing information. For sealed packages, the additional
URL specifies the code source URL from which the package was loaded.

Parameters:

name - the package name

man - the Manifest containing package version and sealing
information

url - the code source url for the package, or null if none

Returns:

the newly defined Package object

Throws:

IllegalArgumentException - if the package name duplicates
an existing package either in this class loader or one
of its ancestors

getPermissions

Returns the permissions for the given codesource object.
The implementation of this method first calls super.getPermissions
and then adds permissions based on the URL of the codesource.

If the protocol of this URL is "jar", then the permission granted
is based on the permission that is required by the URL of the Jar
file.

If the protocol is "file" and there is an authority component, then
permission to connect to and accept connections from that authority
may be granted. If the protocol is "file"
and the path specifies a file, then permission to read that
file is granted. If protocol is "file" and the path is
a directory, permission is granted to read all files
and (recursively) all files and subdirectories contained in
that directory.

If the protocol is not "file", then permission
to connect to and accept connections from the URL's host is granted.

newInstance

Creates a new instance of URLClassLoader for the specified
URLs and parent class loader. If a security manager is
installed, the loadClass method of the URLClassLoader
returned by this method will invoke the
SecurityManager.checkPackageAccess method before
loading the class.

newInstance

Creates a new instance of URLClassLoader for the specified
URLs and default parent class loader. If a security manager is
installed, the loadClass method of the URLClassLoader
returned by this method will invoke the
SecurityManager.checkPackageAccess before
loading the class.